Research Of Volatile Organic Pollutants Removal From Air By Potted Plants

Formaldehyde is one of major indoor organic pollutants. Becauseformaldehyde is harmful to health of indoor residents, formaldehyde removalfrom indoor air is helpful to reduce the healthy risk of city residents. In thisarticle, the dynamic chamber incubation was used to quantitatively studyformaldehyde removal by three kinds of potted plants, i.e., spider plant, aloeand golden pothos. Formaldehyde dehydrogenase in the shoots of three plantspecies was extracted, purified and determined, which was used to identifybiological mechanism of formaldehyde removed of the shoots. The resultsshowed that formaldehyde removal capacities of the shoots appeared as:spider plant> golden pothos> aloe. At the same light intensity, theformaldehyde removal capacities of all shoots increased with formaldehydeconcentration. The orders of formaldehyde removal capacities were same withthe orders of FDH activities, indicating that formaldehyde removal by theshoots are mainly based on FDH activities in them. In addition, formaldehyde removal capacities of the shoots of potted plants in daytime were higher thanin the nighttime under the same formaldehyde concentration.Benzene is the second of major indoor organic pollutants. In the article, astudy was conducted for investigating the effect of benzene on formaldehyderemoval by the plant shoots when the potted plants were fumigatedsimultaneously in gaseous formaldehyde and benzene. The results showed thatformaldehyde removal capacities of the shoots of potted plants increased withgaseous benzene fumigation （ca.15ppm）. Because benzene degradation abilityof golden pothos was stronger than of spider plant, the increment offormaldehyde removal capacity of golden pothos was faster than of spiderplant when they were fumigated simultaneously in formaldehyde and benzene.In addition, toluene was a main industrial and indoor pollutant. Thetoluene removal abilities of three plant species were studied when the tolueneconcentrations were lower. Toluene removal capacities of potted plants werestudied under the different toluene concentrations. The contributions of shootsand soil for formaldehyde removal were studied, respectively. The resultsshowed that spider plant, aloe and golden pothos all had obvious tolueneremoval abilities under the lower concentration (＜1100mg m^-3). At the samelight intensity, toluene removal capacities of the potted plant-soil systems risedgradually with increasing initial toluene concentration. For the same pottedplant and system, the toluene removal capacities in the daytime weresignificantly higher than in the nighttime. At the same light intensity and inlet toluene concentration, the order of toluene removal capacities of plant-soilsystems is spider plant> aloe> golden pothos. The capacities of tolueneremoval for the shoots of three plant species were positively correlated withinlet toluene concentration. The results demonstrated that gaseous toluene canbe significantly removed by the shoots. In the daytime, the shoots hadsignificantly higher capacities of toluene removal than in the nighttime. Thetoluene removal capacity of shoots of aloe expressed on the basis of unit masswas lowest. The toluene degradation rates of potted plant system and soilsystem of spider plant were decreasing with the rise of toluene inletconcentration. And the effect of inlet toluene concentration on degradationrates of aloe and golden pothos can be negligible.